Radioprotection by Podophyllum hexandrum in the liver of mice: A mechanistic approach

To evaluate radiation protection offered by the extract of Podophyllum hexandrum, expression of various cytoprotective proteins was studied using liver of Swiss albino Strain 'A' male mouse by immunoblotting. Induction of heat-shock factor-1 (HSF-1), led to up-regulation of heat-shock protein-70 (HSP-70) upon P. hexandrum (200 mg/kg b. wt.; i.p. 50% ethanolic extract) treatment 2 h before irradiation (10 Gy) as compared to sham-irradiated control. Translocation of free nuclear factor kappa B (NFκB) from cytoplasm to nucleus was found to be inhibited upon P. hexandrum treatment. An increase in Bcl-2, proliferating cell nuclear antigen (PCNA) along with a decrease in p53, caspase-3, apoptosis inducing factor (AIF) expression was observed in the mice treated with P. hexandrum. The present study indicated that P. hexandrum extract provides protection from radiation by modulation of expression of the proteins associated with apoptosis.